In Python, the dict data structure is the conventional key-value structure. E.g., you might store a list of names as keys and have their phone numbers as values. Valentin Ignatev wrote this amusing post on X: It is indeed widely believed that, in the strict sense, the dict data structure and its companion, the set data structure, are O(1), meaning that as you increase the size of the data structure, the time to insert or query a key remains constant. Let us examine the claim. A hash ...

Two decades ago to the day , I made the switch from Macromedia Fireworks to the GNU Image Manipulation Program: Why? Well for one thing I really don’t have the finances as a lowly uni student to buy new licences all the time, not to mention the uncertain future of the aformentioned [sic] program after Macromedia was bought out by Adobe, and the fact that Fireworks isn’t a universal binary yet Talk about dating myself in a paragraph! Macromedia seems like a quaint, distant memory now,...

This blog is part of a series exploring the technologies and principles shaping the future of simulation. Simulation is a broad word. Perhaps too broad. Depending on who you ask, it can mean a desktop trainer, a fixed-base simulator, a full flight simulator, mission rehearsal, or a test environment for future systems. These are all simulations, but they are built differently and serve different use cases. What they have in common is complexity and the need for precision. Effective flight s...

it is your primary job as a founder to find people who care about the problem you’re solving, tell them about your solution, and convert them to get sales. one reliable method that has been working well is to steal engagement from people talking about the exact problem I’m solving already. i.e. using social media to find people who’ve engaged with posts on my topic and reaching out to them. Here’s how that worked: almost a 2.5x better response rate! Tbh, this almost feels ...

Exploring the performance of byte-pair encoding by optimizing a GPT-2 tokenizer. Exploring the performance of byte-pair encoding by optimizing a GPT-2 tokenizer.

“Workslop” is when your colleagues or bosses communicate with you by pasting big chunks of AI-generated text. The core problem with workslop is that the effort involved is asymmetrical , like a denial-of-service attack : it takes almost no effort to produce text with AI, but it still costs effort to read 1 . Here are some ways to protect yourself. If you have enough authority or social capital, you can and should simply tell them “hey, don’t do that” (for instance, if you’re a ...

I started writing Logic for Programmers because there weren’t any good resources on logic for, uh, programmers. Now that the book’s out, the new problem is that there aren’t any good free resources on logic for programmers. So, to solve that problem (and maybe hype the book a little), I converted the second chapter of LfP into a blog post. All footnotes are editorial comments not present in the book. I started writing Logic for Programmers because there weren’t any good resources on log...

There’s a widespread belief that artificial superintelligence (ASI) is inevitable. In this post, I argue that this is false, and believing it is upstream of a lot of bad discourse. Why do people believe it? It’s easy to believe. Samuel Butler , already in 1863, observed that machines are improving faster than humans are improving. Today, AI systems are gaining capabilities much faster than humans: in five years we went from systems that can barely string together a sentence to auto...

Why do so many calendar apps offer Sunday as the first day of the week? It's not the first day of the week, it's the last. Why is that even an option FFS? Thanks for reading this post via RSS. RSS is ace, and so are you. ❤️ You can reply to this post by email , or leave a comment . Why do so many calendar apps offer Sunday as the first day of the week? It's not th...

0.0 Context setting It’s Wednesday 2 September in Portland, Oregon, where it was the first day back at school which also meant it was time to start raining again. We made it on time! That was a big achievement, back pats and handshakes all around everyone. I started writing this episode a good four days ago on 29 August, and jeez has it been weighing on my mind in a very you should have finished this and sent it already sense. For anyone with the belief that writing this newsletter is e...

Anthropic publish the system prompts for their Claude consumer applications ( Claude.ai and the Claude mobile apps - sadly not for Claude Cowork or Claude Code). I love that they do this, and that they share not just the current prompts but historic changes to their prompts as well. They used to keep all of the prompts on a single page, but when I checked today I noticed they had re-arranged those prompts into an index page and then a page per model - here's the page for Haiku 4.5 fo...

When I last visited the National Museum of Scotland, they had an ~A5 booklet of 10 ideas of things to do in an art gallery. I love the idea of a guide that helps you navigate a gallery space. Yesterday, I decided to make a zine in a similar vein, except with some of my own tips for exploring galleries. In the process of making this zine, I realised that I may one day want to write another version that is more edited. There may even be space for me to make multiple zines: one for admiring the arc...

Static Allocation, Constant Work Sep 2, 2026 In reply to this email: Memory Safety’s Hardest Problem named something I’d hit but couldn’t articulate. Your case is a pointer into one union variant surviving a write of a different variant, so live typed pointers end up reading bytes that belong to something else now. Last year I wrote a limit-order matching engine and shipped a use-after-free: a cancelled order was released back to the pool while it was still linked into its ...

Cultivation of the Vines, Henri Martin Kudzu is a plant that was once introduced from East Asia to the eastern United States as a way to combat soil erosion. But, kudzu, once introduced, grows aggressively and can overtake sidewalks, houses, foundations, and even trees. The only way to kill kudzu is to prune it aggressively, as a concentrated strategy enacted together by all the people who live near where the kudzu grows. You know where I’m going with this. An app feature, once...

In building an NTP time demo on old Macs for VCF Midwest , I came across RFC 867 and RFC 868 , for the 'Daytime' and 'Time' Protocols, respectively. My first exposure to any form of network time was when I upgraded from a used PowerBook 180c to my first 'new' computer, a Power Mac G3, in 2000. With the introduction of Mac OS 8.5, Apple added a 'Network Time Server' option in the Date & Time Control Panel. In building an NTP time demo on old Macs for VCF Midwest , I came across RFC ...

What's up on the small web? August 2026 roundup 2026-08-30 12:15 Summer rolls on, and the small web had a busy month: a major Lagrange release, a new graphical client for Android and desktop, terminal tools crossing v2.0, and some good community debates. Here is a roundup of what happened on the small web, the smolnet, and around the Gemini protocol in August 2026. Geminispace past 5,000 known capsules On August 24, Lupa (Stéphane Bortzmeyer's Gemini crawler) published a fresh snapshot:...

Mathematicians are witnessing a profound shift in their field. AI systems are now producing proofs, spotting connections between distant fields, and, in a few cases, solving problems that had stumped mathematicians for decades. The pace of progress over the past several months has raised challenging questions: What can AI systems actually do? And what happens to the more human… Source Mathematicians are witnessing a profound shift in their field. AI systems are now producing proofs, spottin...

The difference between a medicine and a poison is dosage. Often we talk about certain habits, in programming or life, are good or bad. But few things are simple binaries. Some vary with context: reading a book is a good thing sitting in my garden, but not while driving my car. But another variable is dosage: a little pain-killer salves my headache, but too much will kill me. The importance of dosage was noticed by a 16th century Swiss physician called Paracelsus. His quote was or...

Half of all US job postings now name a salary. 50.4% of US postings on Indeed carried explicit wage or salary information in July 2026, the highest monthly reading in a series that starts in January 2020. This page collects salary transparency statistics by country, sector and law, plus what employers and applicants report doing about it. Every figure carries its measurement and period. Key Salary Transparency Statistics 50.4% of US job postings on Indeed contained explicit pay informati...

Ben Brubaker has a new Quanta essay Does Computer Science Need Computers ?  Despite the title (and authors generally don't choose their titles), Brubaker's essay really addresses the question as to whether computer science is about computers. He starts with Dijkstra's apocryphal quote "Computer science is no more about computers than astronomy is about telescopes." This is the wrong analogy: computers are not the telescopes, they are the stars. You just have to use a broad definition of comput...

I started off this year writing a lot, and wanted to keep up the pace. I did good at first! And then… I didn’t manage to. In some ways, this is because I have just been super busy! I’ve never had less free time, and I’m okay with that. There’s a tremendous amount of good things going on in my life. But it’s also put this whole Claude Code series in an awkward spot, because things have been changing so rapidly, that it’s been hard to keep up. And I also need to figure out what i...

About a year ago, I was offered a presentation slot at the WeAreDevelopers World Congress in Berlin. I rarely take speaking engagements, especially international ones, but this one arrived at just the right time, the right place, and with the right person – I said yes, on the contingency that Ben Dumke-von der Ehe joins me in the presentation. Ben is an early community hire at Stack Overflow who lives in Berlin. We both had something important we wanted to talk about, with slightly diffe...

Our Moon as seen by the Galileo spacecraft when it flew past on December 7, 1992. Image: NASA Where did our Moon come from? The origin of Earth’s cosmic companion is a fundamental question in planetary science. From Galileo’s first telescopic observations of the Moon to humans walking on its surface, our understanding of its origins has come a long way. Yet it’s far from complete. Over the decades, scientists have proposed multiple hypotheses to attempt explaining how the Moon came to...